Assertion (A): Vasa efferentia develop from rete testis.
Reason (R) : Sperm conduction takes place by the ciliary current

Options

A. Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion(A).
B. Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
C. Assertion (A) is true but reason (R) is false.
D. Assertion (A) is false but reason (R) is true.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Vasa efferentia develop from rete testis."
- The vasa efferentia are a series of small ducts that connect the rete testis to the epididymis.
- The rete testis is a network of tubules located in the testis where sperm is collected from the seminiferous tubules.
- Since the vasa efferentia are directly connected to the rete testis, it is correct to say that they develop from it.

2. **Understanding the Reason (R)**:
- The reason states that "Sperm conduction takes place by ciliary current."
- Sperm movement through the male reproductive tract is facilitated by the action of cilia present in the epithelial lining of the ducts.
- The ciliated cuboidal epithelium in the walls of the vasa efferentia and other ducts helps in moving the sperm along the reproductive tract.

3. **Evaluating the Truth of Both Statements**:
- Both the assertion and the reason are true. The vasa efferentia indeed develop from the rete testis, and sperm conduction does occur via ciliary action.

4. **Assessing the Relationship Between Assertion and Reason**:
- The reason explains how sperm is conducted through the ducts, which supports the assertion regarding the development of vasa efferentia from the rete testis.
- Therefore, the reason is a correct explanation of the assertion.

5. **Conclusion**:
- Based on the analysis, both the assertion and the reason are true, and the reason correctly explains the assertion.

### Final Answer:
- The correct option is: **Both assertion and reason are true, and reason is the correct explanation of assertion.**

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